U.S. Pat. No. 4,912,096 to Sudilovsky discloses a method for preventing or treating depression employing an angiotensin converting enzyme inhibitor which is ceranapril (SQ29,852), zofenopril or fosinopril.
The use of captopril, an angiotensin-converting enzyme inhibitor, for treating depression is disclosed in the following references:
Deicken, R. F., "Captopril Treatment of Depression," Biol. Psychiatry, 1986; 21:1425-1428;
Zubenko, G. S., "Mood-Elevating Effect of Captopril in Depressed Patients," Am. J. Psychiatry 141:110-11, 1984;
Germain, L. et al, "Treatment of Recurrent Unipolar Major Depression with Captopril," Biol Psychiatry, 1988; 23:637-641;
Giardina, W. J. et al, "Positive Effects of Captopril in the Behavioral Despair Swim Test," Biol. Psychiatry, 1989; 25:695-702;
Bosio, A. et al, "Antidepressant Activity of ACE-Inhibitors," TIPS, Vol. 8, pp 329-330, 1987 (Abstracts of 141st Annual Meeting of the American Psychiatric Association, Montreal, Canada, May 7-12, 1988), discloses that captopril has antidepressant activity while enalapril does not. "These results indicate that ACE inhibitor activity is not related to psychotropic effect . . . ."
U.S. Pat. Nos. 4,046,889 and 4,105,776 to Ondetti et al discloses proline derivatives, including captopril, which are angiotensin converting enzyme (ACE) inhibitors useful for treating hypertension.
U.S. Pat. No. 4,337,201 to Petrillo discloses phosphinylalkanoyl substituted prolines, including fosinopril, which are ACE inhibitors useful for treating hypertension.
U.S. Pat. No. 4,374,829 discloses carboxyalkyl dipeptide derivatives, including enalapril, which are ACE inhibitors useful for treating hypertension.
U.S. Pat. No. 4,452,790 to Karanewsky et al, discloses phosphonate substituted amino or imino acids and salts thereof and covers (S)-1-[6-amino-2[-[hydroxy(4-phenylbutyl)-phosphinyl]oxy]-1-oxohexyl]-L-pr oline (ceranapril, SQ 29,852). These compounds are ACE inhibitors useful in treating hypertension.
U.S. Pat. No. 4,316,960 to Ondetti et al, discloses ether and thioether mercaptoacyl prolines which are ACE inhibitors useful in treating hypertension. This Ondetti et al patent covers zofenopril
U.S. Pat. No. 4,931,430 to Sudilovsky et al, discloses a method for preventing or treating anxiety employing an ACE inhibitor in combination with a calcium channel blocker.
Angiotensin converting enzyme inhibitors and 5-HT.sub.3 (5-hydroxytryptamine.sub.3) receptor antagonists have previously been shown to improve the basal performance of laboratory animals in habituation paradigms and also to overcome the impairment induced by scopolamine (Costall et al (1989), "The effects of ACE inhibitors captopril and SQ29,852 in rodent tests of cognition." Pharmacol. Biochem. Behav. 33; 573-579; Barnes, J. M., et al (1990), "The effects of ondansetron, 5-HT.sub.3 receptor antagonist, on cognition in rodents and primates." Pharmacol. Biochem. Behav. (35; 955-961).
Buspirone, a drug that interacts with serotonin receptors in the brain, is known for its use in treating anxiety (PDR, 1990, p. 1308).
Zacopride which also interacts with serotonin receptors in the brain, is known for its use as an anti-emetic.